This invention provides improved material handling apparatus particularly adaptable for its releasable application to small, relatively lightweight vehicles. Embodiments have particular advantage for use in connection with farm-type vehicles such as agricultural loaders and will be so described, but only for purpose of illustration and not by way of limitation.
Material handling equipment identifiable as an agricultural loader is exemplified by the Series 22 Agricultural Loader made by Dunham Lehr, Inc. This particular loader comprises conventional lift arms anchored at their inner ends to a vehicle to carry a bucket-type material handling device in pivotal connection with their outer ends. Controls are included for raising and lowering the arms and for tilting movements of the bucket. Apparatus of conventional construction such as this lacks adequate outreach capability and cannot provide for positioning and operation of the bucket so as to achieve adequate load leveling capability.
An improved form of lifting and loading apparatus for use in connection with vehicles such as that of the type evidenced by the Dunham Lehr loader has been disclosed in the Schmiesing Material Handling Equipment subject of application for U.S. patent Ser. No. 875,901, filed Feb. 7, 1978, now abandoned. The apparatus of that application provides improvements in outreach and leveling capabilities of lift arm assemblies and therefore significantly advances the art in this respect. The present invention is a second generation advance of the basic concepts of the aforementioned Schmiesing application. It provides improved apparatus for controlling a material handling device by embodiment thereof in connection with lift arms through the medium of a most stably mounted sliding carriage which is sensitively controlled and has its movements in correspondence with and relative the mounted material handling device so as to achieve a maximum utility thereof.
As will be seen, the present invention answers the need for a lift arm assembly which is simply constructed and most stably controlled to achieve extended outreach of the material handling device which it carries and in a manner to make such apparatus most efficient and satisfactory in use and adaptable to a wide variety of applications. More than this, economy is inherent therein.
Additional prior art of which applicant is aware that in applicant's opinion bears pertinence to the subject matter of this invention is found in the U.S. Pat. Nos. 3,390,794 and 3,967,744. These patents feature ideas for extensible boom constructions but their disclosures do not constitute an arrangement of a stabilized sliding carriage and controls therefor and for a mounted material handling device as provided by the present invention. Nor are the material handling devices thereof under the type of precise and firm control as contemplated by the present invention. Nor do they enable the leveling capabilities inherent in the simple structure achieved utilizing the improvements of the present invention.